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Message-ID: <cb24c3dfb707fd361a3e64489b8b68e1e3dbaa07.camel@sipsolutions.net>
Subject: Re: [PATCH v3] cfg80211: Handle driver updated MU-EDCA params
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Muna Sinada <msinada@codeaurora.org>
Cc:     linux-wireless@vger.kernel.org, j@w1.fi
Date:   Mon, 11 Apr 2022 15:45:36 +0200
In-Reply-To: <1641512609-29774-1-git-send-email-msinada@codeaurora.org>
References: <1641512609-29774-1-git-send-email-msinada@codeaurora.org>
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On Thu, 2022-01-06 at 15:43 -0800, Muna Sinada wrote:
> Add necessary functions and attributes to receive updated MU-EDCA
> parameters from driver and send to user space, where management
> frame are updated to reflect latest parameters.
> 
> The updated parameters from driver are part of an AP mode feature
> where firmware determines better MU-EDCA parameters based on channel
> conditions. The updated parameters are used and reported to user space
> to reflect in AP management frames. These dynamic parameter updates
> are offloaded to firmware for better user experience, thus details on
> algorithm are not provided. This is a driver specific feature, thus
> no IEEE80211 spec references.
> 

So, I think this is missing tracing? Earlier I thought you had it, but
that was in mac80211 -- I thought you had both so I said you can remove
it, but it looks like you should have it in cfg80211 perhaps.

More importantly though, shouldn't we have some kind of opt-in flag, so
userspace actually can tell the driver that it's willing to accept this?
As it is, the driver might update it without userspace ever reacting,
since this needs a corresponding hostapd change. Wouldn't this cause
problems? Do you really not care at all about any users who might be
running a slightly older version of hostapd? So maybe hostapd should set
an attribute (even this one as a flag) somewhere to opt in to receiving
this, and thereby promising it will use it?

johannes